Grinding machine and method of grinding



Aug. 3, 1937. l. R. SHUE 2,089,040

GRINDING MACHINE AND METHOD OF' GRINDING:

Filed July 5, 1935 2 Sheets-Sheet 1 @Ze J3. 5hae ,3 Y

9 I. R: SHUE 2,089,040

GRINDING MACHINE AND METHOD OF GRINDING Filed July 5, 1935 2Sheets-Sheet 2 Patented Aug. 3, 1937 UNITED STATES PATENT OFFICE IngleR. Shue, Beloit, Wis assignor to Gardner Machine Company, South Beloit,111., a corporation of Illinois Application July 5, 1935, Serial No.29,793 13 Claims. (CI. 51-111) The invention relates generally togrinding machines and more particularly to a grinding machine employinga grinding disk adapted to grind articles on the face thereof.

In grinding operations, it is desirable to remove stock from the articlebeing ground as fast as possible in order to keep the cost of theoperation down. However. when stock is removed at a high rate, thearticle tends to become heated. With the high rates attained in thepresent state of the art, such heating tends to reach such an extentthat it is detrimental to the article being ground. Cooling of thearticle by providing a flow of coolant across the face of the grindingdisk has been employed. But even this has proved insufllcient in manyinstances, chiefly because of the fact that the coolant is incapable ofreaching in sufficient quantity the surface being ground where the heatis generated. The coolant may be liberally supplied, but the contact ofthe article being ground with the grinding face sweeps the bulk of thecoolant aside. Thus, the surface being ground comes in contact with verylittle, if any, coolant during the entire operation.

. The general object of the invention is therefore to supply coolant toa grinding disk in such a manner that it may come in contact with thesurface being ground in adequate quantity during the grinding operation.

Another object is to provide a grinding machine constructed so thatcoolant may be forced through the grinding disk to the grinding facethereof to cool surfaces being ground thereon.

A further object is to provide a grinding machine having a grinding diskconstructed to permit the flow of coolant therethrough, and a means forsupporting and rotating the disk constructed to cooperate with the diskin supplying coolant thereto whereby the rotation of said means and thedisk induces sumcient pressure on the coolant to effectively force itout between the surface being ground and the grinding disk.

Another object resides in providing an im- 5 proved method of grinding.

. Other objects and advantages will become apparent from, the followingdescription taken in connection with the accompanying drawings, inwhich:

50 Figure 1 is an elevational view of a grinding machine embodying thefeatures of the invention.

Fig. 2 is an enlarged fragmentary perspective view, partially insection, of one of the grinding 55 wheel structures of the machine shownin Fig. 1.

Fig. 3 is a fragmentary sectional view taken on the line 3-3 of Fig. 2.

Fig. 4 is a fragmentary sectional view taken on the line 4-4 of Fig. 2.

Fig. 5 is a-perspective view of the disk supporting means shown in Fig.2.

,Fig. 6 is a fragmentary perspective view, P rtially insection, of amodified form of grinding wheel structure.

Fig. '7 is a perspective view of the rear face of the grinding diskshown in Fig. 6.

Fig. 8 is a fragmentary sectional view taken on the line 8-8 of. Fig. 6.g

Fig. 9 is a fragmentary sectional view taken on the line 99 of Fig. 6.

A grinding machine embodying the featuresof the invention comprisesgenerally a grinding disk constructed to permit the flow of fluidcoolant therethrough from the rear face of the grinding disk to itsgrinding face, thus providing a construction whereby fluid may beconducted directly to the surface being ground to carry away the heattherefrom as it is generated. Preferably fluid is supplied to the diskby passages cooperatively formed by a supporting wheel carrying the diskand the disk itse'lf,.said passages exending radially and receivingfluid through the spindle which carries the wheel. Thus upon rotation ofthe disk and wheel, the fluid is centrifugally forced outwardly throughthe passages and then through the disk so that it is supplied underpressure to the surface being ground.

The coolant is preferably a liquid but may be merely air which serves tocool the disk and work piece, and to blow out particles of the disk andwork piece removed in the operation of grinding.

, The invention is illustrated as embodied in a grindingmachine of thedouble-disk type shown in Fig. 1, in which work may be ground on twoparallel surfaces at the same time by passing between a pair of. opposeddisks. ,As shown herein, the machine comprises a base l0 providing apair of spaced ways II on which are mounted a pair of spindle heads,indicated generally at 12 and including grinding wheel structures ofwhich grinding disks l3 are a part. The spindle heads are adjustablelongitudinally on the ways ii to vary the space between the disks toaccommodate work pieces of different size. Below the disks 13, themachine may be provided with Each spindle head I2 is illustrated ascompris-' ing a head frame I! having a pair of spaced portions It inwhich a spindle I1 is journaled. The spindle l1 projects beyond theinner of the spaced portions and is provided at its inner end with acollar I6 to support a wheel IS. The latter is adapted to have securedthereto the grinding disk I: in a usual manner. The spindle |1 may bedriven by a pulley 20 mounted thereon between the spaced portions l6.

In the present instance, the disk illustrated comprises two layers, thefront layer, indicated at 2|, being made of moulded abrasive material,while the rear layer, indicated at 22, is made of moulded materialhaving embedded therein a wire reinforcing mesh 23 and a plurality ofnuts 24 adapted to receive bolts extending through the supporting wheel|3 to secure the disk rigidly thereto. The grinding disk has the usualannular shape to provide a relatively large aperture 25 at its center.

The chief feature of the inventionis to construct the disk l3 so thatfluid coolant 'may be conducted therethrough from the rear face to thegrinding face. Thus, the coolant may be led into direct contact with thesurface on the work piece being ground to carry off the heat as it isgenerated. To this end, the disk is provided with a plurality ofrelatively small apertures 26 extending through the disk.

At the rear of the disk is means to supply fluid coolant to theapertures 26. Preferably said means comprises passages cooperativelyprovided by the supporting wheel and the disk, said passages beingherein shown as a plurality of grooves 21 closed by the disk and taperedto provide sumcient flow for two apertures 26. The grooves 21 preferablyextend radially from the center of the supporting wheel out to theapertures 26 and are closed at their outer ends. Thus, when fluid 4.coolant is supplied to said grooves, it is centrifugally forcedoutwardly and through the apertures 26 so that it will strike thesurface being ground and be forced out between said surface and thegrinding face of the disk. It will thus be supplied directly to thesurface being ground in adequate quantity to carry off the heatgenerated.

Preferably the fluid coolant is conducted to the grooves 21 through thespindle l1, the latter having an internal bore 36 for this purpose. Atthe end of the bore 30 and overlying the inner ends of the grooves 21 isa chamber formed by a cap 3| having a'flange 32 abutting the face of thesupporting wheel. The flange 32 thus holds the cap proper spaced fromthe supporting wheel and the end of the spindle so that the coolant mayflow out of the bore 30 in the spindle and into the grooves 21. The cap3| is shaped to fit snugly in -the central aperture 25 of the disk, 50that the disk and cap completely cover the grooves 21, and is secured tothe supporting wheel as by screws 33.

As a further means of supplying coolant to the grinding surface of thedisk, the cap 3| may be provided with one or more apertures 34 to permita flow of coolant over the grinding surface from the central aperture25.

The grinding disks are preferably enclosed by a hood (not shown) toconfine and collect the coolant as it leaves the disks. With oppositelyfacing disks as shown in Fig. 1. and with liquid coolant, the latterpassing out of the aperture 26 which are not covered by the work piecetends to spray against the grinding surface of the op-' posite disk aswell as over'the work piece. Thus.

with the coolant confined by a hood the work piece is thoroughly cooled.

In the modified form shown in Figs. 6 to 9, .the

grinding disk, indicated at 40, is so constructed in its flange toprovide communication from the bore 30' of the spindle to the grooves4|.

To supply coolant to the interior of the spindle, a cap 45 vis placedover the outer end of the spindle and is held against rotation by thehead frame. The cap 45 is connected to a source of coolant supply by apipe 46 and a connecting tube 41 which is preferably flexible to allowfor adjustment of the spindle head. The source of coolant supply may bea pump 46 driven by a separate motor or from the spindle drive.

In operation, the two disks I3 are adjusted to the desired distanceapart and a work piece is secured to the work table H to be movedbetween the disks. Upon rotation of the spindle, the fluid coolantsupplied to the bore 30 in the spindle from the source 41 is forced bycentrifugal force outwardly from the chamber formed by the cap 3|,through the grooves 21 in the supporting wheel, and through theapertures 26. The coolant flowing from the apertures 26 passes over thegrinding surface of the disk and, as the surface being ground passesover the apertures 26, the coolant comes in direct contact therewith tocarry oi the heat. Thus, the coolant is supplied directly to the surfacebeing ground. At the same time, coolant is permitted to flow from theapertures 34 in the cap 3| and thence over the grinding surface of thedisk. The centrifugal action on the coolant tends to assist or evensupplant the pump 46. The flow of coolant also carries off the particlesremoved from the disk and work piece in the operation of grinding toprevent glazing the disk.

In the modified form shown in Figs. 6 to 9, the chamber formed by thecap 3| is in communication with the grooves 4 by means of the notches 42cut in the flange of the cap. The grooves 4| are in the rear face of thedisk and communicate with the apertures 26 in a similar manner to thegrooves 21 in the supporting wheel in the first form.

From the above description, it will be apparent that I have provided agrinding machine in which fluid coolant forced under pressure directlyagainst the surface being ground by conducting the coolant is soarranged that the rotation of the disk centrifugally forces the coolanttherethrough, the coolant being supplied to said mean through a bore inthe spindle.

I claim as my invention:

1. In a grinding machine, the combination of a rotatably' drivengrinding member having a plurality of apertures therethrough, asupporting member for rotating and supporting said grinding member, oneof said members having radially extending grooves in its facecooperating with the-other member to provide passages extending from thecenter of rotation to said apertures, said passages being closed attheir outer ends, and means to supply fluid to said, passages at theirinner ends.

2. In a grinding machine, the combination of a rotatably driven grindingdisk having a plurality of apertures leading from the rear face 7 fromits center, a supporting'wheel for said disk to the grinding face, asupporting wheel for said disk having a plurality of grooves inits'front face extending radially to said apertures and closed at theirouter ends, said grooves being covered by said disk to provide closedpassages, v

and means to supply fluid to said grooves.

3. In a grinding machine, the combination of a rotatably driven grindingmember having a plurality of apertures leading from the rear face to thegrinding face, a supporting member for said grinding member, one of saidmembers having a plurality of radially extending grooves closed by theother member to provide a plurality of radially extending passagesleading to said apertures, said grooves terminating at said apertureswhereby the outer ends of said passages are closed, means providing achamber in communication withthe inner ends of said grooves, and meansto supply fluid to said chamher.

4. In a grinding machine, the combination of a grinding disk having aplurality of apertures leading from the rear face to the grinding facethereof, a supporting wheel for said disk, said disk having a pluralityof grooves in its rear face leading from the center to said aperturesand closed by said supporting wheel, and means for supplying fluid tothe inner ends of said grooves.

5. A grinding machine comprising, in combination, a grinding memberhaving a plurality of apertures therethrough, a'supporting member havingsaid grinding member secured to its face, one of said members havingradial grooves in its abutting face which are closed by the other memberto provide passages extending from the center to said apertures, aspindle for driving said. supporting member, said spindle being hollowwith its interior communicating with said passages, and means to supplyfluid to the intesaid spindle to said apertures, means for supply-,

ing fluid to the interior of said spindle at the other end thereof, andmeans for driving said spindle and positioned intermediate the endsthereof.

'7. A grinding machine comprising, in combination, a grinding diskhaving a relatively large aperture at its center and a plurality ofrelatively'small apertures spaced from the center,.a supporting wheelhaving said disk secured to one face thereof'and cooperating with saiddisk to provide a plurality of passages leading from said centralaperture to said small apertures, a hol-* low spindle having said wheelmounted on one end thereof, a cap mounted in said central aperture andshaped to provide a chamber communieating with said passages and theinterior of said spindle, and means to supply fluid to the interior ofsaid spindle. l

8. A 'g'rin'dingjmachine comprising, in combination, an annular grindingdisk having a plucooperating therewith to provide a plurality ofpassages extending from the interior of said annulus to said apertures,a hollow spindle having the supporting wheel thereon, means forsupplying fluid to the interior of said spindle, and means within saidannulus providing communication between said passages and the interiorof said spindle and having a plurality of holes openfluid may flow overthe grinding face of said disk from the interior of saidannulus and fromsaid apertures.

9. A grinding machine comprising, in combination, a grinding disk havinga relatively large central aperture and a plurality of relatively smalleccentrically located apertures, a hollow spindle, a supporting wheelforthe disk mounted on one end of said spindle and cooperating with saiddisk to provide a plurality of passages leading from said centralaperture to said eccentric apertures, a cap positioned within saidcentral aperture and having a flange abutting the face of the supportingwheel to providea chamber communicating with the interior of saidspindle and with said passages, and means to supply fluid to theinterior of said spindle.

10. Agrinding machine comprising, in combination, a grinding disk havinga relatively large central aperture and a plurality of relatively smalleccentrically located apertures with radial grooves in the rear faceextending from said cenlow spindle, a supporting wheel mounted on oneend of said spindle and having the disk secured to 'the face thereofthereby covering said grooves,

a cap mounted within said central aperture and having a flange abuttingthe face of the supporting wheel to provide a chamber in communicationwith the interior of said spindle, said flange being radially notchedtoprovide communication between said chamber and said grooves, and meansto supply fluid to the interior of said spindle.

11. In a grinding machine, the combination of a rotatable grindingmember having a plurality of apertures leading from the rear face to thegrinding face thereof, a supporting member for said grinding member, oneof said members having radial grooves providing in conjunction with theother member a plurality of radial passages extending from adjacent thecenter of rotation to said apertures, and means for supplying fluid tosaid passages adjacent the center of rotation whereby rotation of saidmembers will centrifugally force the fluid outwardly through saidpassages and said apertures.

12. A supporting wheel of the character described having a plurality ofgrooves in its face extending from the center of the wheel radially andterminating shortof the periphery of the Wheel and adapted to be closedto provide fluid conducting passages leading to a point adjacent theperiphery thereof.

13. A grinding disk having a plurality of eccen tricallylo'catedapertures. leading from its rear face to its grinding face and, aplurality of radial grooves in'its rear face leading to said aperturesand adapted to be covered by a supporting wheel to provide passages for.fluid.

INGLE R. SHU'E.

